Real-time CNC OEE calculation enhances Continuous Improvement Program

CNC Lathe Productivity Problem: Trajan Scientific and Medical, an international supplier of precision medical devices desired a practical means to accurately measure and improve the setup process of their Swiss-style CNC lathes, and to document the effectiveness of Continuous Improvement initiatives. Manual data collection methods were impractical, and their lathes did not have provision for serial data collection such as MTConnect.

Off the Shelf OEE tracking Solution: Trajan installed an OEE reporting system from Production Process. The system collects production and performance data from MDT-150 Operator/Machine Interfaces, one connected to each lathe.

Tapping into the lathe “discrete” electrical operating signals for the MDT-150 was simple said David Elks, Trajan’s General Manager (SciMed Precision Division): “From unused G and M program codes we identified one that activated a lathe physical function we didn’t require; We then modified the CAD/CAM post processor to output the specific G code in the correct sequence in the CNC program. Then, it was a simple task of connecting the lathe electrical output to the input of the MDT.

The MDT-150 automatically records downtime when no part has been produced for a part-specific cycle time, and prompts the Operator to enter a reason for the downtime through the MDT keypad. Additionally, a simple proximity provides an out stock signal from the bar feeder to track that specific downtime when it occurs.

Bottom line: 1,941 setup hours saved, with 3 month ROI. Said David: “From the OEE data we identified the key elements involved in setting up our CNC machines. As a result we implemented procedures to reduce setup time and realized an annual, overall plant setup time reduction of 40% or 1,941 hours.”